According to an example, a failed component in a fault-tolerant memory fabric may be determined by transmitting request packets along a plurality of routes between the redundancy controller and a media controller in periodic cycles. The redundancy controller may determine whether route failures for all of the plurality of routes have occurred within a number of consecutive periodic cycles. In response to determining that route failures for all of the plurality of routes have occurred within a number of consecutive periodic cycles, the media controller is established as failed. In response to determining that route failures for less than all of the plurality of routes have occurred within the number of consecutive periodic cycles, a fabric device is established as failed.

A system and method for providing erasure code protection across multiple storage devices. A data switch in a storage system connects a plurality of storage devices to a remote host. Each storage device is also connected to a controller, e.g., a baseboard management controller. During normal operation, read and write commands from the remote host are sent to respective storage devices through the data switch. When a write command is executed, the storage device executing the command sends a copy of the data to the controller, which generates and stores erasure codes, e.g., on a storage device that is dedicated to the storage of erasure codes, and invisible to the remote host. When a device fails or is removed, the controller reconfigures the data switch to redirect all traffic addressed to the failed or absent storage device to the controller, and the controller responds to host commands in its stead.

Aspects of the present disclosure relate to systems and methods for automatic management of digital data volumes logically maintained in a dynamically scalable fault tolerant matrix. The data volumes may be distributed across a cluster of connected server nodes included in a cloud computing architecture. A processing device in communication with the matrix ensure that read/write request may be serviced by the matrix to access the digital data maintained within the data volumes may be continuously accessed, regardless of data volume failure that are missing, offline, or in a failed state.

A method of operating a storage device may include determining a fault condition of the storage device, selecting a fault resilient mode based on the fault condition of the storage device, and operating the storage device in the selected fault resilient mode. The selected fault resilient mode may include one of a power cycle mode, a reformat mode, a reduced capacity read-only mode, a reduced capacity mode, a reduced performance mode, a read-only mode, a partial read-only mode, a temporary read-only mode, a temporary partial read-only mode, or a vulnerable mode. The storage device may be configured to perform a namespace capacity management command received from the host. The namespace capacity management command may include a resize subcommand and/or a zero-size namespace subcommand. The storage device may report the selected fault resilient mode to a host.

Embodiments herein provide a method for controlling operations of a Redundant Array of Independent Disks (RAID) data storage system comprising a host device and a plurality of solid-state drives (SSDs). The method includes performing, by the at least one SSD, recovery of lost data by performing the auto-rebuild operation. The method also includes performing by the at least one SSD, the auto-error correction operation based on the IO error. The method also includes creating a snapshot of an address mapping table by all SSDs of the plurality of SSDs in the RAID data storage system. The auto-rebuild operation, the auto-error correction operation and the creation the snapshot of the address mapping table are all performed without the intervention from the host device.

Provided are mechanisms for promptly or gradually migrating data from a read-only disk in a storage system to a replacement disk, where, during gradual migration, data is migrated when it is requested of the read-only disk.

Techniques are provided for processing user input/output (I/O) write requests in a fault-tolerant data storage system (e.g., a RAID storage system) by selecting between performing a degraded write operation or a write operation to spare capacity, when the fault-tolerant data storage system is operating in a degraded mode. A method includes receiving a user I/O write request comprising data to be written to a RAID array operating in a degraded mode, and determining whether spare capacity has been allocated for rebuilding missing data of an inaccessible storage device of the RAID array and whether a missing data block, which is associated with I/O write request, has been rebuilt to the spare capacity. A degraded write operation is performed without using the spare capacity, when the missing data block, which is associated with the data of the I/O write request, has not been rebuilt to the allocated spare capacity.

Techniques for data processing involve: determining, from a disk array, a target disk used for data reconstruction of the disk array; and sending, to an indicating apparatus associated with the target disk, an indication that the target disk is used for the data reconstruction. In this way, such techniques can indicate to the user that the target disk is being used for data reconstruction to remind the user not to remove or move the target disk, thereby ensuring completion of the data reconstruction. Such a technique may improve data storage equipment operation by preventing user interference.

An autonomous RAID data storage system includes a RAID storage controller device that communicates with RAID data storage devices in order to configure them to perform direct command operations with each other. A first RAID data storage device receives a multi-step command from the RAID storage controller device and performs a first subset of operations associated with the multi-step command, while also performing direct command operations with a second RAID data storage device in order to cause it to perform a second subset of operations associated with the multi-step command, When the first RAID data storage device completes the first subset of operations and receives a first completion communication from the second RAID data storage device that indicates that the second subset of operations are completed, it sends a second completion communication to the RAID storage controller device that indicates that the multi-step command is completed.

Provided are mechanisms for promptly or gradually migrating data from a read-only disk in a storage system to a replacement disk, where, during gradual migration, data is migrated when it is requested of the read-only disk.